static-initializer

You'll probably ask, why would I want to do that - it's because I'm using a class (from an external library) which does stuff in its static initializer and I need to know whether it's been done or not. I looked at ClassLoader , but didn't find anything that looked useful. Any ideas? Colin Hebert You can use the ClassLoader.findLoadedClass() method. If it returns null, then the class isn't loaded. This way you don't load the class if it wasn't already loaded. WARNING : This code doesn't really work here, in the system ClassLoader, findLoadedClass() is protected, you need to override it with

I have a few classes as shown here public class TrueFalseQuestion implements Question{ static{ QuestionFactory.registerType("TrueFalse", "Question"); } public TrueFalseQuestion(){} } ... public class QuestionFactory { static final HashMap<String, String > map = new HashMap<String,String>(); public static void registerType(String questionName, String ques ) { map.put(questionName, ques); } } public class FactoryTester { public static void main(String[] args) { System.out.println(QuestionFactory.map.size()); // This prints 0. I want it to print 1 } } How can I change TrueFalseQuestion class so

I read about the SIOF in the faq-lite and still I really don't understand why the issue happens. I have a static library(.a) and I use that library to use its static const data member object type. Then that static const data member object type I use and assign to a global variable(object). But it seems that global variable is empty when I use that global variable to my main or to any local function. I know obviously that my issue is SIOF but I really don't understand why my static const data member object was not initialized. It was static library so I guess when we created our static library

By default, Sun's JVM both lazily loads classes and lazily initializes (i.e. calls their <clinit> methods) them. Consider the following class, ClinitBomb , which throws an Exception during a static{} block. public class ClinitBomb { static { explode(); } private static void explode() { throw new RuntimeException("boom!"); } } Now, consider how to trigger the bomb: public class Main { public static void main(String[] args) { System.out.println("A"); try { Class.forName("ClinitBomb"); } catch (Exception e) { e.printStackTrace(System.out); } System.out.println("B"); ClinitBomb o2 = new ClinitBomb

What is the best and cleanest way to do this? Specifically, I need some code in a static initializer block to run in that class, but I'd like to make this as clean-looking as possible. Loading != Initialization. You want your class to be initialized (this is when static blocks executed, among other things). An excerpt from the Java Language Specification says: A class or interface type T will be initialized immediately before the first occurrence of >any one of the following: T is a class and an instance of T is created. T is a class and a static method declared by T is invoked. A static field